Consistent with earlier remarks made for bond length comparisons, little if any improvement results in moving from the 6-3IG to the 6-311+G basis set for Hartree-Fock, local density and density functional models, but significant improvement results for MP2 models. [Pg.118]

experimental results for the H—O bond lengths and the H—O—H bond angle, and include a discussion of the comparison in your report. [Pg.111]

We shall examine the simplest possible molecular orbital problem, calculation of the bond energy and bond length of the hydrogen molecule ion Hj. Although of no practical significance, is of theoretical importance because the complete quantum mechanical calculation of its bond energy can be canied out by both exact and approximate methods. This pemiits comparison of the exact quantum mechanical solution with the solution obtained by various approximate techniques so that a judgment can be made as to the efficacy of the approximate methods. Exact quantum mechanical calculations cannot be carried out on more complicated molecular systems, hence the importance of the one exact molecular solution we do have. We wish to have a three-way comparison i) exact theoretical, ii) experimental, and iii) approximate theoretical. [Pg.301]

The pyrimidine ring is virtually flat. Its corrected bond lengths, as determined by a least-squares analysis of the crystal structure data for a unit cell of four molecules, are shown in formula (2) (60AX80), and the bond angles derived from these data show good agreement with those (3) derived by other means (63JCS5893) for comparison, each bond... [Pg.58]

Table 2 Comparison of Bond Lengths and Angles of Monoheterocycles... |

Table 4 Comparison of Bond Lengths and. Angles of Dibenzo Heterocycles... |

Table 5 Comparison of C—X Bond Lengths for Parent Heterocycles and their Dibenzo Derivatives... |

Figure 1.25 A comparison of bond lengths in the complexes RuCl2(PPh3)3 and RuHCl(PPh3)3. |

Careful comparison of Pt-P bond lengths for the series trany-Pt(Pcy3)2X2 (X = H, Cl, Br, I) with those for p-any-Pt(PR3)2X2 (PR3 = PMe3 or PEt3) shows a more definite increase in Pt-P with anion size for the cyclohexyl-phosphine complexes (Table 3.16) believed to be owing to intermolecular X- H and X- C non-bonded interactions arising from overcrowding [151]. [Pg.244]

© 2019 chempedia.info